The present invention relates to a process for the separation of anti VIII:C antibodies present in a liquid, such as blood plasma. More specifically, it relates to insoluble polymer or copolymer supports usable for the selective purification of the specific antibodies of factor VIII:C, i.e. the anti VIII:C antibodies present in the blood plasma, such as that of a patient suffering type A hemophilia. Thus, in the case of type A hemophiliacs who have had repeated blood transfusions, in general anti VIII:C antibodies form, which neutralize the coagulating activity of the transfused factor VIII:C. The presence of these antibodies leads to serious difficulties. Moreover, in order to treat hemorrhages in A type hemophiliacs, it is generally necessary to carry out exchanges of the blood plasma, immediately followed by VIII:C factor injections, in order to obtain a normal hemostasis and this treatment often has to be continued for a long time, as a function of the state of the patient. The leads to serious problems, because it is difficult under such conditions to maintain the indispensable constituents of the patient's blood plasma at the desired levels. Moreover, the risks of infection by viruses, such as that of hepatitis or LAV/HTLV3 virus become greater with the number of transfusions.
In addition, for some years now, research has aimed at processes for the direct purification of the plasma by the adsorption of disturbing elements on an appropriate support. In the case of B type hemophiliacs, it has been possible to carry out this purification by adsorption of specific antibodies factor IX, i.e. anti IX antibodies, on a protein A bonded by covalency to agarose, as is described by I. M. Nilsson et al in Blood, Vol 58, No 1 (July 1981), pp 38 to 44. The protein A reacts with the Fc part of the immunoglobulins and when it is bonded with sepharose, it can be used as an immunosorbent for isolating the immunoglobulins G and consequently the antifactor IX. However, the total immunoglobulin content of the thus treated plasma represent no more than 1/5 of its original value, which leads to certain problems. Furthermore, present research has been directed at immunosorbents able to selectively separate the desired antibodies, specifically those present in the blood of hemophiliacs.
In the case of antiVIII:C antibodies, present research has not made it possible to selectively and quantitatively separate these antibodies. Thus, consideration has been given to carrying out said separation by selective adsorption by means of a chromatographic gel on which is immobilized the VIII:C factor. However, this method is unusable, because the VIII:C factor very rapidly loses its antigen properties.
For several years now, research has been directed at the use of inert supports, to which are fixed appropriate compounds making it possible to give the support a particular affinity, e.g. for certain constituents of the blood. Thus, French patent No. 83/10773, filed on June 29, 1983 by the C.E.A, illustrates the use of polymers of this type for the separation and purification of thrombin. In this case, arginine, nitroarginine or one of the derivatives thereof, such as methyl ester is fixed to the polymer or copolymer for giving the support said affinity with respect to thrombin.